Measured amounts of various fluid substances are increasingly commonly dispensed in relatively small flexible packages often composed of plastic or foil. The fluids include a wide variety of products, including foodstuffs such as condiments (for example ketchup, mustard, relish and the like), personal care products such as shampoos and skin creams, cleaning products such as various packaged “wipes,” and pharmaceutical products such as medications.
A typical example is the ubiquitous single serving ketchup pack, which is generally formed of two sheets of foil or plastic, superimposed over one another and then sealed together around the periphery, with a notch or other means to facilitate tearing one edge away from the container. The user tears open the container, dispenses the condiment, and then disposes of the package.
Such packaging, while relatively simple and inexpensive, poses numerous drawbacks in this most simple embodiment. Firstly, the simplest such package contains no integral means for directing or spreading the dispensed fluid. In particular, thick fluids tend to be dispensed as a bolus, leaving the user to find an implement to spread the bolus, or otherwise to improvise with the possibly unsanitary outside of the now empty package to form a crude spreader. Alternatively, thin fluids tend to be dispensed in a difficult to control stream.
Second, the package can be quite difficult to open, particularly for those with arthritic hands or otherwise compromised grip strength. This difficulty is at least in part caused by the fact that, in the simplest conventional embodiments of this package, it is necessary to tear away one of the sidewalls of the packaging in order to release the contents. Such a sidewall must be relatively strong in order to contain the contents under normal handling conditions, which may include accidental compression. Even a small amount of moisture or skin oil on the surface of the packaging can make gripping and tearing the generally small package nearly impossible. It is extremely common to see frustrated users of such packaging using their teeth to open ostensibly manually “tear open” packages. Such a technique poses obvious aesthetic and hygienic issues.
Third, velocity of the fluid as it is expelled from the packaging varies with viscosity of the fluid, the amount of sidewall opened and the pressure applied. Anyone who has squeezed a ketchup package with only a pinpoint opening in its side can testify to the extreme distances the condiment can be propelled.
Various attempts have been made over the years to address these problems, with varying degrees of success. The creation of packaged, pre-moistened towelettes facilitates spreading but requires a handling of the dispensed contents. Pre-loaded, disposable, swabs obviate handling, but contain very small amounts of dispensable liquid. The need to facilitate spreading a dispensed liquid was addressed by means of an integral roller in U.S. Pat. No. 5,577,851 to Koptis. The '851 patent teaches a sponge applicator attached to a tube dispenser that contains a quantity of a substance, such as painter's spackle, to be dispensed. After use, the sponge applicator is designed to be removed, cleaned, and returned to the tube dispenser. The reuse of the sponge applicator raises issues of potential hardening and chemical or bacterial deterioration of the sponge. This makes the '851 applicator unsuitable for use with products such as those intended for human consumption, where bacterial contamination may be devastating. Such problems can be overcome with single use, or “throw away” sponge applicators, but the complexity of the '851 device makes it ineffective on a cost basis for single use containers.
A similar attempt to provide an integral spreader is seen in U.S. Pat. No. D363,377, which provides a roller atop a dispensing container. The roller spreads the dispensed fluid, but is subject to the same cleaning and hygienic drawbacks posed by the sponge pad applicator of the '851 patent.
Efforts to produce an integral spreading means suitable for single use containers have exhibited mixed success. For example, U.S. Pat. No. 6,007,264 to Koptis teaches a variation on the simplest form of packaging, that of two superimposed sheets sealed together around their periphery, with the provision of peelable flaps along one edge of the package. The user peels back the flaps, pulling apart one sealed edge of the package and thus exposing the contents. The peeled back flaps, at an approximate 90-degree angle to the package, thereby provide a butterfly wing type spreader for spreading the contents. Such a design overcomes any need to clean or re-use the spreading device, as the entire unit is disposable.
However, the utility of the '264 design has been found to be directly proportional to the viscosity of the fluid dispensed. For example, fluids with a high viscosity, such as ketchup or heavy creams, tend to be dispensed as a discrete bolus, whereupon they can be effectively smeared about the intended surface by the butterfly wings. However, experience has shown that liquids of low fluid viscosity, such as some pharmaceutical preparations and other relatively thin liquids, tend to be dispensed from the opened container in a stream, as opposed to a bolus, and run out of the flap or wing spreading area before they can be effectively spread.
The '264 device attempts to counter this propensity by disclosing an embodiment wherein an absorbent foam applicator is either applied in two pieces to the opposing flaps or is applied in a single piece bridging the flaps. Such embodiments are designed to provide an absorbent surface area to facilitate the spreading of the fluid dispensed. However, experience with the base design has revealed that it is marginally effective for this purpose. In practice, separate foam applicators that do not bridge the container opening may increase surface area and absorbency for spreading, but do nothing to retard the sudden flow of material from the ruptured packaging. Even in the embodiment wherein the absorbent pad bridges the opening, practice has shown that when the pouch is squeezed and the frangible seal breaks, the contents of the pouch burst through the seal and the liquid tends to squirt through the absorbent pad, rather than being gently absorbed into the pad as intended.
As to the second problem, that of facilitating the opening of the container, various methods have been proposed. The '264 device provides enlarged tear flaps that are intended to facilitate gripping the container, however, the problem of tearing away a relatively strong sidewall of the container remains. In essence the present invention is directed to improvements for the Koptis '264 device and all teaching contained in U.S. Pat. No. 6,007,264 are herein incorporated by reference.
In U.S. Pat. No. 4,921,137 to Heijenga, the container is equipped with an enlarged ear-like structure that facilitates grip. In addition, the '137 device contains, within the ear-like structure, a preformed channel portion that attempts to address the third problem, that of dependably producing a large enough egress channel for the dispensed material so as to minimize excessive pressure effects, such as uncontrolled squirting of the contents. However, the '137 device makes no provision to address the problem of spreading a bolus of dispensed liquid.
U.S. Pat. No. 6,117,123 to Barney discloses a flexible container that provides for the storage and mixing together of diluents and medicaments. The container incorporates multiple compartments, separated by preferentially peelable seals, in which the diluents and medicaments are stored. The peelable seals are ruptured by manipulation of the container to thereby mix the components together for delivery through standard I.V. equipment to a patient. The seals are constructed such that the seal between the diluent and medicament compartments is preferentially ruptured such that a liquid medicament and a diluent are always mixed before the combined solution is accessible for administration.
The prior art fails to disclose a disposable, unit dose container for liquids of varying viscosity that allows for easy opening, without touching the container contents, where the liquid is dispensed into an unsealed area behind the foam pad in such a manner that the liquid is easily dispensed. Such a dispensing pouch must be inexpensive and easy to manufacture, maintain the integrity of the liquid until dispensing, and must reliably dispense the liquid without being unduly susceptible to accidental release, yet be easy to open. Further, the absorbent pad may be protected by a cover that can be easily removed just prior to dispensing, and the design of the pad should facilitate easy and even spreading of the container contents.